Nano-structured polymer composites and process for preparing same

Abstract

A process for preparing a polymer composite that includes reacting (a) a multi-functional monomer and (b) a block copolymer comprising (i) a first block and (ii) a second block that includes a functional group capable of reacting with the multi-functional monomer, to form a crosslinked, nano-structured, bi-continuous composite. The composite includes a continuous matrix phase and a second continuous phase comprising the first block of the block copolymer.

What is claimed is: 
     
       1. A process for preparing a polymer composite comprising reacting (a) a multi-functional monomer and (b) a block copolymer comprising (i) a first block and (ii) a second block that includes a functional group capable of reacting with the multi-functional monomer, to form a crosslinked, nano-structured, bicontinuous composite comprising a continuous matrix phase and a second continuous phase comprising the first block of the block copolymer, wherein the multi-functional monomer comprises a metathesis-reactive monomer and reacts with the second block of the block copolymer in the presence of a metathesis catalyst. 
     
     
       2. A process according to  claim 1 , further comprising treating the composite to selectively remove the first block of the block copolymer in the second continuous phase to form a plurality of pores. 
     
     
       3. A process according to  claim 2 , wherein the pores have an average pore diameter of about 1 to about 500 nanometers. 
     
     
       4. A process according to  claim 2 , wherein the pores have an average pore diameter of about 10 to about 50 nanometers. 
     
     
       5. A process according to  claim 2 , comprising treating the composite with a chemical etchant. 
     
     
       6. A process according to  claim 1 , wherein the multi-functional monomer is a multi-functional, ethylenically unsaturated monomer. 
     
     
       7. A process according to  claim 1 , wherein the metathesis-reactive monomer comprise a cyclic olefin. 
     
     
       8. A process according to  claim 7 , wherein the cyclic olefin is selected from the group consisting of dicyclopentadiene, cyclooctene, and combination thereof. 
     
     
       9. A process according to  claim 7 , wherein the metathesis catalyst comprises a functional-group tolerant metathesis catalyst. 
     
     
       10. A process according to  claim 9 , wherein the functional-group tolerant catalyst comprises second generation Grubbs catalyst. 
     
     
       11. A process according to  claim 1 , wherein the first block of the block copolymer is selected from the group consisting of a polylactide block, a sulfonated polystyrene block, and combinations thereof. 
     
     
       12. A process according to  claim 1 , wherein the second block of the block copolymer includes an ethylenically unsaturated functional group capable of reacting with the multi-functional monomer. 
     
     
       13. A process according to  claim 1 , wherein the second block of the block copolymer comprises a norbornenyl group capable of reacting with the multi-functional monomer. 
     
     
       14. A process according to  claim 1 , wherein the second block of the block copolymer comprises a copolymer of styrene and norbornenylethylstyrene. 
     
     
       15. A process according to  claim 1 , wherein the block copolymer further comprises a third block. 
     
     
       16. A process according to  claim 1 , wherein (a) the multi-functional monomer is selected from the group consisting of dicyclopentadiene, cyclooctene, and combination thereof; and (b) the block copolymer is selected from the group consisting of a polylactide-poly (styrene-co-norbornenylethylstyrene) block copolymer, a sulfonated polystyrene-poly(styrene-co-norbornenylethylstyrene) block copolymer, a polylactide-poly(dimethyl acrylamide)-poly (styrene-co-norbornenylethylstyrene) block copolymer, and combinations thereof. 
     
     
       17. A process according to  claim 1 , comprising reacting the multi-functional monomer and the block copolymer in the presence of a homopolymer polylactide. 
     
     
       18. A process according to  claim 2 , wherein the composite is in the form of a nano-porous or barrier membrane. 
     
     
       19. A process according to  claim 18 , wherein the membrane is a water purification membrane, ammonia separation membrane or fuel cell membrane. 
     
     
       20. A composition comprising a crosslinked, nano-structured, bicontinuous composite that includes a continuous matrix phase and a second continuous phase, wherein the continuous matrix phase comprises nanometer-sized domains, said nanometer-sized domains comprise a second block of a block copolymer, and the second continuous phase comprises a first block of the block copolymer, wherein the first block is selected from the group consisting of a polylactide block, a sulfonated polystyrene block, and combinations thereof. 
     
     
       21. A composition according to  claim 20 , wherein the composite comprises a plurality of pores. 
     
     
       22. A composition according to  claim 21 , wherein the pores have an average pore diameter of about 1 to about 500 nanometers. 
     
     
       23. A composition according to  claim 21 , wherein the pores have an average pore diameter of about 10 to about 50 nanometers. 
     
     
       24. A composition according to  claim 21 , wherein the composite is in the form of a nano-porous or barrier membrane. 
     
     
       25. A composition according to  claim 24 , wherein the membrane is a water purification membrane, ammonia separation membrane or fuel cell membrane. 
     
     
       26. A composition comprising a crosslinked, nano-structured, bicontinuous composite that includes a continuous matrix phase and a second continuous phase, wherein the composite comprises the reaction product of (a) a multi-functional monomer and (b) a block copolymer comprising (i) a first block and (ii) a second block that includes a functional group capable of reacting with the multi-functional monomer, and the second continuous phase comprises the first block of the block copolymer, wherein the multi-functional monomer comprises a metathesis-reactive monomer and is capable of reacting with the second block of the block copolymer in the presence of a metathesis catalyst.